Valve did a sneaky, small-but-significant thing recently: it expanded its " Top Sellers " list on Steam to include one hundred games. The sales leaderboard doesn't tell us exactly how many copies a game sold, but it gives us a vague idea of how well certain games are doing on Steam in a given moment.

It's an inherently misleading metric—take that as a disclaimer. Still, as we sit in the shadow of some of 2012's biggest releases, I'd like to take a crack at gleaning what we can from this moment in time.

2K's having a great end of the year.

The $50 pre-sale of XCOM is outselling everything but Borderlands 2 on Steam. We might be able to chalk that up to fairly generous pre-purchase incentives (which could include a free copy of Civ 5 if enough people pre-buy it). It might be mild evidence that demos still work, too. Borderlands 2's high concurrent user count over the past few days (reaching 123,758 last weekend) is also evidence that 2K will win the weeks connecting September and October on Steam.

Digital pre-orders are a thing.

XCOM isn't the only thing-you-can-buy-but-can't-play-yet doing well. Joining the unreleased are Dishonored at #7, War of the Roses at #12, Football Manager 2013 at #17, Company of Heroes 2 at #29, and Hitman Absolution at #51. Even though there's no chance of a game going out of stock, Steam users don't seem to mind putting money down in advance, especially if they're rewarded with bonus content or a small discount for doing so.

Where are the MMOs? Oh, right.

Zero MMOs appear in today's top 100. I might consider that unsurprising—we wouldn't expect too many people to be picking up competitors while Guild Wars 2 and Pandaria are drawing the attention, and neither are available on Steam. Still, it's a little surprising not to see RIFT ($10) or EVE Online: Inferno ($20) popping up anywhere.

Call of Duty remains a PC fixture.

The sense that Call of Duty remains a fixture for PC gamers is supported by SteamGraph data. Some form of Call of Duty make up 10 whole entries of the Steam's top 100. Many of those are map packs, but the performance of Call of Duty: Black Ops - Mac Edition (#41) is interesting to me. It released yesterday, September 27, and it's outperforming stuff like Civ V: GOTY and Natural Selection 2. Modern Warfare 3 is 50% off until October 1, and it's sitting comfortably at #5.

DayZ continues to have a long tail.

I don't think Arma 2: Combined Operations (what you need to play DayZ) has left the top ten of Steam's Top Sellers since it caught on in May and June. It seems to be outperforming other games that released in May and June like Sins: Rebellion (#56), Max Payne 3 (#76), Civ 5: Gods & Kings (#20), and Spec Ops: The Line (unlisted).

Below: the data, captured at 6:05 PM PDT. Ctrl + Fing encouraged.

Top Ten

Borderlands 2

XCOM: Enemy Unknown

Total War Master Collection

Torchlight II

Call of Duty: Modern Warfare 3

Carrier Command: Gaea Mission

Dishonored

Counter-Strike: Global Offensive

Arma 2: Combined Operations

Empire: Total War

#11-25

Castle Crashers

War of the Roses

Borderlands 2 Season Pass

FTL: Faster Than Light

Cortex Command

The Elder Scrolls V: Skyrim

Football Manager 2013

The Elder Scrolls V: Skyrim - Dawnguard

Garry's Mod

Sid Meier's Civilization V - Gods 'n Kings

Dark Souls: Prepare To Die Edition

The Binding of Isaac

Half Minute Hero: Super Mega Neo Climax Ultimate Boy

Left 4 Dead 2

Hell Year! Wrath of the Dead Rabbit

#26-50

F1 2012

Hearts of Iron III: Their Finest Hour

Rome: Total War - Gold

Company of Heroes 2

Total War Shogun 2 - Fall of the Samurai

Sid Meier's Civilization V

Counter-Strike: Source

Borderlands: Game of the Year

Worms Revolution

Total War Mega Pack

Terraria

The Walking Dead

Rocksmith

Call of Duty: Modern Warfare 3 Collection 3: Chaos Pack

Call of Duty: Black Ops - Mac Edition

Binding of Isaac: Wrath of the Lamb

Portal 2

McPixel

Sid Meier's Civilization V: Game of the Year

Total War: SHOGUN 2

The Sims 3

Counter-Strike Complete

Hearts of Iron 3 Collection

The Witcher 2: Assassins of Kings Enhanced Edition

#51-100

Hitman: Absolution

Borderlands

Train Simulator 2013

The Testament of Sherlock Holmes

Medieval II Gold

Sins of a Solar Empire: Rebellion

Orcs Must Die! 2 - Family Ties Booster Pack

Call of Duty: Black Ops II

The Amazing Spider-Man

Orcs Must Die! 2

Saints Row: The Third

Dead Island: GOTY

Natural Selection 2

Orcs Must Die! 2 - Complete Pack

Half-Life 2

Amnesia: The Dark Descent

Rome: Total War - Complete

The Orange Box

Borderlands 2 + Official Brady Guide

Batman: Arkham City GOTY

Arma 2: Operation Arrowhead

Grand Theft Auto IV

Endless Space

Killing Floor

Call of Duty: World at War

Max Payne 3

Call of Duty: Modern Warfare 2

SPORE

I Am Alive

Fallout 3: GOTY

Fallen Enchantress

Valve Complete Pack

Fallout: New Vegas Ultimate Edition

Mount & Blade: Warband

New Star Soccer 5

Portal Bundle

Call of Duty: Modern Warfare 3 Collection 2

Magic: The Gathering - Duels of the Planeswalkers 2013 Expansion

Counter-Strike

Call of Duty: Modern Warfare® 3 Collection 1

Arma 2

Might & Magic Heroes VI - Danse Macabre Adventure Pack

Magic: The Gathering - Duels of the Planeswalkers 2013

Call of Duty: Black Ops

Tony Hawk's Pro Skater HD

STAR WARS: Knights of the Old Republic II

Call of Duty 4: Modern Warfare

Planets Under Attack

Transformers: Fall of Cybertron

Age of Empires III: Complete Collection

Reiterating: We don't know what formula or data drives Steam's Top Sellers rankings. It's probably safest to consider them a representation of what games are selling well in one moment of time on Steam.